What is the "is-ought" problem (also known as Hume's guillotine) and why is it important for ethical reasoning?

Question

Accepted Answer

The philosophical observation that one cannot logically derive moral conclusions (what ought to be) solely from factual premises (what is), highlighting the gap between descriptive and normative claims. The "is-ought" problem, identified by David Hume, observes that it is logically invalid to derive prescriptive moral conclusions (what ought to be the case) solely from descriptive factual premises (what is the case). Simply because something is natural, traditional, or common does not mean it is morally right; and simply because something is rare or unusual does not mean it is morally wrong. This principle is important because it highlights the fundamental gap between facts and values, warns against the "naturalistic fallacy" (deriving ethical norms from natural facts), and reminds us that moral arguments require explicitly stated moral premises in addition to factual claims.

A debate about mandatory ethics courses describes an educational policy question rather than the fundamental logical principle about the relationship between factual claims and moral conclusions. A legal principle about facts and values describes a judicial methodology rather than the philosophical insight about the logical gap between descriptive and normative statements. A medical ethics guideline for treatment decisions describes a clinical standard rather than the foundational philosophical principle about the nature of moral reasoning.

The is-ought problem is a foundational concept in ethical reasoning for the Ethics in America DSST exam. Students should understand Hume's original insight, the naturalistic fallacy, how the is-ought gap affects ethical argumentation, and why ethical claims require normative premises that cannot be derived from empirical facts alone. This concept underpins critical thinking about all ethical arguments students will encounter on the exam.

DSST Ethics in America: Question of the Day

Get a free DSST Ethics in America question every day

Ready for the full DSST Ethics in America? Earn 3 college credits.